Internal-combustion engine



Oct. 7 1-1, 1927.

' 1,645,471 w. D. ARMITAGE INTERNAL COMBUSTION ENGINE Filed Jan. 11.1924 4 Sheets-Sheet' 1 1927" w. D. ARMITAGE INTERNAL COMBUSTION ENGINEFiled Jan. 11. 1924 4,Sheets-Sheet 2 N r 1,645,471 Oct. 11, 1921.ARI-WAGE INTERNAL COMBUSTION ENGINE Filed Jan. 11. 1924 4 Sheets-Sheet 3Oct. 11;. 1927.

1,645,471 W. D. ARMITAGE I INTERNAL COMBUSTION ENGINE Filed Jan. 11.1924 4 Sheets-Sheet 4 .l' F J7 Patented Oct. 11, 1927.

WILLIAM n. ARM ITAGE, or new ."ennronn, MASSACHUSETTS.

INTERNAL-COMBUSTION ENGINE.

Application filedhnuary 11, 1924-. serial No. 685,693.

, This invention relates to internal combustion engines and moreparticularly to en gines of the type'liaving continuously rotatingpistons moving in a cylinder or combustion chamber in the form of acylindrical ring or torus.

One of the objects of this invention is the provision of an internalcombustion en: gine of the type described in which one of the pistonsalways moves in the same direction and at a substantially uniformangular velocity around the cylinder or combustion chamber for any givenengine speed.

Another object of this invention is to provide a pair of opposed pistonsadapted to travel within the combustion chamber at varying speedsrelative to each other,

A further object is to provide an internal combustion engine having amoving system in which there areno parts reciprocating in a directionnormal to the axis of rotation of the main engine shaft and in which therotating system is at all times in true static and dynamic balance.

A still further object is the arrangement 01" an internal combustionengine wherein one cylinder produces the same effect as four cylindersin the normal type of four strokecycle internal combustion engine both.as to power and number of power strokes per revolution.

There is further provided by this invention an internal combustionengine having a toroidal combustion chamber in which are arranged a pairof opposed pistons adapted to cover and uncover the exhaust and intakeports in one of the walls of the combustion chamber and means formaintaining the intake port closed at all times except when the pistonsare inducing a charge of combustible mixture.

Further important features and objects of this invention will becomeapparent to those skilled in the art as my invention is more fullydisclosed in the accompanying specification and drawings.

Broadly and briefly stated, my invention contemplates providing aninternal combustion engine including a stationary combustion chamber inthe form of a hollow torus; a fly wheel adapted for rotation about anaxis concentric with that of the torus and extending through the innerwall of the combustion chamber; a pair of opposed pistons arranged totravel in one direction about said combustion chamber, one of saidpistons being fixed for rotation with said fly; wheel and the second ofsaid pistons being connected to said fly wheel by mechanism permittingthe distance between said pistons to vary between 'fixed limits;stationary means adapted to cooperate with said mechanism for varyingthe distance between said pistons; an intake port; an exhaust port;

and a spark plug.

Inthe drawings accompanying this specificationz i 'Fig. l is a sideelevation of an internal combustion engine constructed in accordancewith my invention;

Fig. 2 is an elevation at rightangles to F gure 1 showing a singlecylinder engine;

Fig; 3 is an elevation showing the right handhalf of the casing, asvshown. in'Figure 2, removed, with the fly wheel and pistonsv inplace andshowing by dotted lines the positions of the stationary cams which aretastened to the removed section;

Fig. i is a section on line 4-4 of Figure 1;

Fig. 5 is a side elevation of the fly wheel;

Fig. 6 is .a partial section on line 66 of Figure 3';

Fig. 7 is a section on line 'Z7 oi Figure3;'

Fig. 8 is an elevation of the inside of the right hand half of theengine casing;

Fig. 9 is a more or less diagrammatic view showing the positions of apair of pistons at the beginning and the end of'the intake stroke; V

F ig. 10 is a similar' view showing the positions of the pistons-at thebeginning and end of the compression stroke;

Fig. 11 is a similar view showing the positions of the pistons at thebeginning and end of the power stroke; and" Fig. 12 is a similar viewshowing the positions of the pistons at the beginning and end oftheexhaust stroke.

Viewed in Figures 1 and 2 my internal combustion engine comprises ingeneral a cylindrical housing or casing 1 composed of two similar interfitti-ng parts 2 and 3 held together by bolts apassing throughbosses spaced about the periphery of the cylinder. Mounting brackets 5are provided whereby the engine may be hung from any suitable support,such as the side frame members of an auton'iotive vehicle to which usemy type of engine may be put. The parts 2 and 3 of the engine casing aresubstantially circular in form and each flat side wall is provided atthe center thereof with a boss drilled to form a bearing for the mainshaft 7 of the engine.

As viewed in Figures 3 and a it will be seen that the engine casing isdivided into four main compartments each substantially circular in form.The chamber 8 which is circular in cross section is a hollow torus andcomprises a combustion chamber in which the pistons 9, 10, 11 and 12 areadapted to travel. The compartments 13 and 14 which substantiallyenclose the combustion chamber are water jackets through which thecooling water is adapted to circulate and carry off the heat ofcombustion from the motor. A cylindrical chamber 15 is adapted to housethe fly wheel 16 and other parts of the motor to be mentioned later andalso provides means for distributing lubricating oil.

The fly wheel 16 which is clearly shown in Figures 3, at, 5 and 6 is ofsubstantially circular form with two diametrically opposite, irregularshaped portions removed. It has an enlarged hub member 17 fitting uponthe tapered section 18 of the shaft 7, is held against rotation inrespect thereto by means of a key 19 and against longitudinal move mentby means of a nut 20 threaded upon the Extending radially from the hub"shaft. member is a thin central web 21 provided with the bosses 22, 22,23, 23 which are drilled for the reception of pivot bolts the use ofwhich will be described later. The fly wheel is adapted to fit through anarrow circular slot 2 1 in the wall of the combustion chamber and ishence provided with a pair of thin sections 25, 25 of a thickness justsufficient to snugly engage the side walls of this slot. Between thesethin sections 25 and the web sections 21 the fly wheel is provided withtwo heavy inner rim portions 26, 26 adapted to fit snugly against theinwardly extending radial flanges 27, 27 bordering the circular slot inthe combustion chamber walls. Inside ofthe cylinder the fly wheelbroadens as shown at 28 snugly engaging the walls of a widened slotwhich is a continuation of the narrow slot 24. This widened portion hasits outer face shaped to conform to the curve of the cylinder wall andit is the object of these various inter-fitting flanges, grooves and soon, to provide a gastight seal between the cylinder and the fly wheel.which, when bathed in oil during normal operation of the motor, willprevent the es cape of the compressed combustible charge and the gasesresulting from the explosion.

Referring to Figure 5 it will be seen that the portions 25 and 26 of thefly wheel are co-extensive and each of substantially 130 extent, whereasthe thickened portion 28 is of approximately 30 extent. Radiating asshown at 34: for the reception of wrist pins 35 by means of which thepistons 9 and 11, which I will hereafter call power pistons, aremaintained in fixed relation to, and for movement with, the fly wheel.

I contemplate providing each explosion cylinder or combustion chamberwith two pairs of pistons, as shown in Figure 3, each pair comprising apower piston 9, 11 connect-ed for movement with the fly wheel and afollowing or explosion piston 10, 12 movable within fixed limits inrespect to the power piston and the fly wheel. These pistons may be ofthe usual construction except that they are shaped to conform snugly tothe curved cylinder wall and are each provided with suitable pistonrings 36 for maintaining the compression.

It be desirable to relieve the walls of the pistons between the ends toreduce the friction on the cylinder walls but a rib 9, 10", 11, 12 isleft on each piston on its outermost face for a purpose to be laterdescribed.

The compartment 37 formed between a pair of pistons such as 9 and 10varies in size during the operation of the motor and corresponds to thecylinder and combustion chamber in the usual type of internal combustionengines. This compartment rotates with the fly wheel during the normaloperation of the engine and successively passes the intake port 38, thespark plug opening 39 and the exhaust port 40 all of which open into theouter wall of the explosion chamber. Before reaching the intake port 38the pistons are spaced as shown at 37 in Figure 3, which is the minimumdistance allowed between these pistons.

Immediately upon the piston 9 fully uncovering port 38 piston 10 isretarded in speed so that before the port 38 is again closed off bypiston 10 the two pistons have separated a maximum permissible distance.which ordinarily corresponds to a compression ratio of about 4 to 1although any desired ratio may be used. The intake port 38 is thenclosed by the rib 10 on piston 10 and as this piston moves forward bythe outer rim 31 of the fly wheel. Upon this happening the piston 10moves forward more rapidly than piston 9 compressing the charge betweenthe two pistons until at the time the compartment 37 reaches the sparkplug opening 39 the pistons are again in the closest position. At thispoint an electric sparktakes place at the spark plug, firing the chargewhich expands and drives the piston 9 forward, the piston 10 beingrestrained against rearward movement by means of latches n best shown inFigure 7.-

The latches 41 include wedges having inclined faces at 2 adapted forreciprocation in recesses 43 in the cylinder walls and having integraltherewith the stop pins 4L1" which are headed over beyond the rear wallsof the recesses to retain the wedges in the position-shown in Fig. 7against the action of the springs 42. The lower ends of these wedges asviewed in Fig. 7 are below the surface of the cylinder walls and withthe inclines facing toward the approaching pistons so that a pistonmoving in the direction of the arrow in Figure 7 will press against thefaces 42 and thus push the wedges all down into the chambers against theaction of the springs 42. Immediately upon the passage of the piston thewedges 41 will be pressed outward into the position shown in Figure 7effectually preventing any reverse movement of the piston.

When under the'infiuence of the explosion charge the pistons 9 and 10have reached their maximum -distance apart the piston 9 begins touncover the exhaust port 4L0 and the piston 10 is caused to againincrease in speed so that before the exhaust port is closed by thepiston 10, the compartment 37 has been reduced to its minimum size thusdriving out the burned gases. The pistons 9 and 10 continue theirforward movement with the compartment 37 remaining a minimum until theintake port 38 is again reached when the cycle of operation is repeated.As shown in Figure 3 the engine is provided with two sets of pistons sothat for each revolution of the fly wheel there are two power strokescorresponding in effect to the usual four-cylinder four-cycle enginewherein there are a like number of power strokes for each revolution ofthe crank shaft.

In order that the explosion pistons 10 and 12 may move at differentspeeds than their corresponding power pistons, I have devised thefollowing mechanism and since it is the same in each case a descriptionof that in connection with piston 10 will suflice for both. A connectingrod 4:4 provided with a forked end 45 its over the boss 22 and pivots ona suitable bolt 46 passing through the connecting rod and fly wheel.Pivoted to the opposite end of this connecting rod is a connecting rodlink 47 journalled at its end remote from the pivot on a wrist pin 4L8fixed within the piston 10. Intermediate the ends of the connecting rodis pivoted a cam bar 49. Pivoted for rotation about a suitable boltthreaded in the boss 23 of the fly wheel is a cam substantiallysegmental in shape, having integral therewith a cam arm 51, which camarm is pivoted at its remote end to the opposite end of the cam bar 49whereby upon rotation of the cam 50 about its pivot 23 motion istransmitted to the cam arm 51, through the cam bar 49, to the connectingrod (i l and since this is pivotcd at its inner end tothe fly wheel,motion is imparted to the piston 10 by means of tl c connecting rodlink, so that the piston moves relative to the fly wheel.

As shown best in Figures 4 and 8 three stationary cams 52, 53 and 54 arearranged against one of the outer walls of the chamber 15 and areadapted to be successively engaged by the inovablecam 50 as it isrotated with the fly wheel, to cause it to revolve about its pivot andmove the piston 10 relative to the fly wheel and the piston 9. These cammembers may be formed integral with the engine casing or may be attachedthereto by suitable fastening means as shown in Figure 8.

Referring now to Figures 9, 10, 11 and 12 the action of these cams willbe explained throughout the cycle of operation of one set of pistons.Figure 9 shows in full lines the positions of the two pistons 9 and 10at the beginning of the intake stroke where it will be seen that thepistons are closest together and as piston 9 fully uncovers the intakeport the cam 50 engages the forward end of the stationary cam 52 in sucha manner as to be rocked backward thereby thus retaining the piston 10almost stationary as the piston 9 moves forward so that the chamber 37enlarged and draws in a charge of combustible mixture through the intakeport 38 which is connected to any suitable type of carburetor. At thetime the intake port is closed off by the piston 10 the two pistons havereached their greatest distance apart and a full charge of combustiblemixture is contained between them. The pistons then move in unison untilthe outer rim 31 of the flywheel has closed the intake port. l/Vhen thepistons are a maximum distance apart the links 49 and 51 are in astraight line and the rear of piston 1-0 just touches the rim 3i.

Referring to Figure 10 it will be seen that as soon as the intake portis closed by the rim 31 the cam 50 engages the stationary cam 53, thecam arm 51 draws the cam bar 49 forward. and with it the connecting rodand piston 10 so that this piston travels at a greater speed than piston9 thereby compressing thecharge between the two pistons whichcompression operation is completed just as the cam 50 leaves the cam 53and the space 37 between the two pistons, now a minimum, is opposite thespark plug.

At this time as shown in Fig. 11 the latch bar l1 drops behind thepiston 10, the cam 50 is released from the cam and the explosion takesplace, piston 10 remaining stationary against the latch 41 while piston9 moves forward delivering its energy to the fly wheel and thence to theload connected to the engine shaft. Throughout this power stroke asshown in Figure 11 the cam member 50 is free to be rotated under theaction of the connecting rod.

Just at the completion of the power stroke as the power piston 9 beginsto uncover the exhaust port 40 the cam 50 engages with the longstationary cam 54 as shown in full lines in Figure 12. This causes theinner end of cam 50 to be retarded thus advancing piston 10 more rapidlythan piston 9 in a similar manner to that which took place during thecompression stroke, as previous ly explained, so that by the time piston10 has closed off the exhaust port 40 the pistons are again at theirminimum distance apart and the waste products of combustion have beenexpelled from between them. The pistons retain this position of minimumdistance apart under the action of the stationary cam 54 until theintake port 38 is again uncovered by piston 9 when the operation isrepeated. It is of course to be understood that a similar action takesplace in connection with pistons 11 and 12 as they pass the variousports.

It will be noted that throughout their complete cycle the pistons 9 and10 ride upon the portion 28 of the fly wheel rim so that the spacebetween the pistons is effectually sealed from the compartment 15 inwhich the cams operate. It will be further noted that the outside rim 31of the fly wheel closes off the intake and exhaust ports except at suchtimes as the compartment 37 between the pistons uncovers this port itbeing noted that the circumferential distance between the two rimsections 31 is just great enough to accommodate the two pistons whenthey are at their maximum distances apart in which condition thesepistons pass the in take port. If desired the forward end of these rimsections 31 may form an abutment limiting the distances between thepistons 9 and 10 in order to reduce any strain upon the cam 50 and itscorresponding movable parts at such times as the pistons move at theirmaximum distance apart.

As explained earlier this motor is adapted to be cooled in theconventional manner by water passing through the jackets 14 and 15surrounding the explosion chamber and I have shown at the intake openingwhereby the water is pumped into one of these water jackets the twoparts of the water jacket being connected together by means of theregistering openings 56. At 57 is shown the outlet for'the water, halfof this opening being in each half of the engine casing so that waterfrom each half may flow out from this outlet. To provide for propercirculation I have shown a water pump 58 which may be of any convenienttype adapted to be driven by the shaft 59 and connected by means ofbevel gears 60 to the main shaft 7. A tube 61 serves to conduct water tothe pump and a pipe 62 conducts it from the pump to the inlet opening55.

Driven from the same shaft as the water pump is an oil pump 63 of anyconvenient type mounted on the lower extension 64: of the casing whichextension contains the compartment or oil sump 65 which can be filledthrough the filler opening 66 closed by a convenient cap 67. The pump 63draws oil from the sump 65 and by means of the pipe 68 branched at 69delivers the oil to the inside of the casing in the compartment 15 justabove the two bearings for the shaft 7. The oil runs down the innerwalls of this compartment, passes over and lubricates the mam bearings,the excess oil forming two pools in the bottom of the compartment 15between its outer walls and the two radial flanges 27 into one of whichpools of oil the cam arm 51 and cam bar 49 are adapted to dip, thussplashing the oil in a manner similar to that accomplished by the largeends of the connecting rods in the ordinary type of splash lubricationin automotive type internal combustion engines thus maintaining a finespray or mist of oil within the compartment 15 which lubricates all ofthe working parts of the motor. The pool of oil in the oppositecompartment overflows the flange 27 and serves to lubricate the flywheel where it fits through the slot in the cylinder wall keeping thisjoint tightly sealed. The excess oil at this point flows on to thecylinder walls and is picked up by the pistons, which are thus freshlylubricated each time before undergoing the intake, compression, powerand exhaust strokes as previously explained. The excess oil flows outthrough the bore 70 and is thus returned to the sump or reservoir 65.

In order to maintain a water, gas and oil tight seal between the twohalves 2 and 3 of the engine casing, it is contemplated that theirmeeting surfaces be ground to an exact plane in order that they shallhave a perfect fit when brought together and clamped by the bolts t. Asan alternative a thin compressible gasket may be placed between themeeting faces. The engine is assembled by fitting the fly wheel on itsshaft, connecting all parts to the fly wheel that move there with andthen assembling the two halves of the engine casing around the flywheel, bolting the two halves of the casing together and applying theintake and exhaust manifolds, spark plug, etc., not shown.

In order to properly time the explosion I contemplate using the ignitioncontacter 71 which is mounted upon the outer wall of the engine housingand has an insulated spring contact member 72 which extends through thewall of thehousing and is adapted to be engaged by the cam 50 to close acircuit at the time when the compartment 37 is exactly centered belowthe. spark plug opening 39. The usual type of ignition coil, supplying ahigh tension current to the spark plug, may be used and since this iswell known, I do not deem it necessary to illustrate or describe ithere.

It will thus be seen that I have provided an internal combustion enginewhich is of very simple design, has a minimum number of parts and weighsmuch less than an engine of the conventional type of the samehorsepower. It can be arranged to add any number of units desired intandem, acting on the same main shaft to obtain any power desired andany unit may be removed for repair without disturbing the remainingunits. Owing to its inherent balance this motor is absolutelyvibrationless at all speeds. The

, number of moving parts in a motor according to my invention is verysmall, there being but two gears used, to drive the oil and water pump,and in any single unit there are less than two dozen moving partsincluding the water and oil pumps.

It will further be understood that during the explosion stroke the poweris at all times applied at a uniform distance from the main shaft andwith a maximum lever arm which is not the case in the usual type ofinternal combustion engines. This motor furthermore has no. dead centeras is customary in the usual reciprocating type of' I do not wish to belimited to this particular form.

Having thus described the invention what is claimed as new and desiredto be secured by Letters Patent is:

1. In an internal combustion engine of the class described, a toroidalcombustion chamber, a flywheel rotatably mounted about the axis of saidchamber and extending therein to the outer wall thereof, a power pistonrigid with said flywheel, an explosion piston, a piston rod connectingsaid explosion piston to a point near the center of said flywheel, acam, having a cam-bar, pivoted to said flywheel and a link connectingsaid cambar and an intermediate point in said connecting rod.

2. In an internal combustion engine of the class c escribed, a toroidalcombustion chamber, a flywheel rotatably mounted about the axis of saidchamber, extending through the inner wall thereof and contacting withthe outer wall thereof, a power piston rigid with said flywheel, anexplosion piston, a piston rod connecting said explosion piston to apoint near the center of said flywheel, a cam, having a cam-bar, pivotedto said flywheel, a link connecting said cam-bar and an intermediatepoint in said connecting rod, and a stationary cam adapted to be engagedby said cam on said flywheel.

3. In an internal combustion engine of the class described, a toroidalcombustion chamber, a flywheel rotatably mounted about the axis of saidchamber and extending therein, a power piston rigid with said flywheel,an explosion piston, apiston rod connecting said explosion piston to apoint near the center of said flywheel, a cam, having an integralcambar, pivoted to said flywheel, a link connecting said cam-bar and anintermediate point in said connecting rod, and a pair of sta tionarycams adapted to be successively engaged by opposite faces of said cam onsaid flywheel to rotate it in opposite directions.

In testimony whereof I hereunto afix my signature.

WILLIAM D. ARMITAGE.

